Friction shock-absorbing mechanism



Feb. s', 1927.

J. F. OCONNOR FRICTION SIXTXOCK BSORBNG MECHANISM I Filed March 9, 1925 l 2 sheets-sheet 1 Feb. s, 1927.

. J. F. OCONNOR FRICTION SHOCK ABISORBING MECHANISM med March 9, '1925 2 sheets-sheet '2 .1 41,14 l nf y 'JOHN' lr. ocoNNoR, or CHICAGO, ILLINOIS, Assreuonffro Minna, -1i\c.,oF

CHICAGO, ILLINOISQA CORPORATIONYOF DELAWARE.

FRICTION snocnnnsomim MECHANISM.

Appiication ineafiaarch e', 1925., seriai N. 13,947.

This invention relates to improvementsjin v friction shockabsorbing mechanisms.

Y @ne object of the invention is to provide a friction shock absorbing mechanism lespecially adapted for railwaydraftV riggings,

wherein are obtained light resistance during initial or preliminary action, and a change into a heavierjnal frictional resistance 'during the compression stroke.

Anotherobfect of the inventionis to provide, in a mechanism of the character yindi- Y cated, a wedge system so arranged that during initial actionr and for a predetermined Y portion of lthe compression stroke, true# 15l lwedge or spreadingA action isabsent, during vwhich time the actuatingv force'is transmittedA from the main wedgejthro-ugh the diverging friction blocks to the spring resistance, a true wedging or spreading-action being set up aftera predetermined compression and upon engagement of vthemain wedge and the friction shoes.l

@ther objects. of the invention will more fully'and clearly appear. from the description, and claims hereinafterfollowing. *l In the drawings, forminga part of thisy specification, Figure l is` alongitudinal, sectional view of a portion of a railway draft 'rigging showing my improvements in con- Anection therewith, the section through the friction elements corresponding to two intersecting planes at an angle of 120 to each other. Figure 2Ais a front and elevational view of the shock absorbing mechanismV proper. Figure 3 1s a vertic'al,rtransverse,V sectionalview corresponding substantially to the line 3&3 of Figure 1. And Figure l isa detailed,.and elevational viewlof .three intermediate friction vblocks used in connection with my improved mechanism.

In said drawings, 10-1() indicate channel` shaped center or Vdraft sills, to the inner faces of which are secured front stoplugs Y 1111 and rear stop lugs 12-12. The in-A ner end of the drawr bar isv indicated at'13 to which is connected a hoodedyoke 14C-of well known form. Arlhe shock absorbing mechanism proper, as well as a front follower 15, is disposed within the yoke. The yoke and parts therewitliin are operatively 'sup-Y ported by a detachable saddle plate 16 secured to the dra-ft sills.

- The improved shock absorbing mechanism proper, as shown, comprises broadly, a

spring cage casting Ara friction ,shell B;-

three friction-shoes@ C and C., afwedge 13,141"andEQl a main spring follower F; an auiriliary follower plate G; a wear plate H; twin arranged main springs J; Vanda retainerholt K. i n

The spring cage casting A is of i.^ectangul ,i

lar box-like form having horizontally disblock D; three intermediate friction blocks l y i nerof the usual follower.V At the forward end, the side walls 19 are provided with opposed inwardlyV extending l flanges 21. Spaced inwardly from the ianges are a Vpair* of vertically `disposed ribs 22, the flanges andv ribs together defining vertical guide slots 28, for a purpose hereinafter described.

VAs clearly shown in Figure 1,*the sides of `the spring cage A are left open to .permit lateral insertion of the main springsJ. The friction shell B is of substantially cylindrical form and has a pair of lateral flanges 24 adjacent the rear end thereof, the

flanges being adaptedrto be received in the slots` 23 of the casing A to retain the friction shell against longitudinal movement and rhold the same in assembled relation with the cage. '.lhefriction shell is provided ,with

l three substantially cylindrical interior friction surfaces 25,convergmg slightly inwardly of the shell, the surfaces being so disposed that they will form a` substantially complete circleat the inner end of the shell.

.The three friction shoes C, C and C which vare preferably in the, form ofl castings are of likeV construction except as. lhereinafter pointed` out. Each shoe C is formed with Y anouter true cylindrical friction surface A125, adaptedk to cooperate with one ofthe friction .surfaces 25 of the friction shell.

Each shoehas a pair of inclined faces 26l land 27 on the side nearesttlie longitudinal axis of the mechanism, the Vinclined faces 26 and 27 being-arranged respectively atk the outer and innerends of the shoe. As cle-arly shown in Figure 1', the inclined faces 27 are inclined ata sharperA angle to the'V longitudinal axis of the gear than"A are the faces 26. The faces 26v of the twoishoes C extend at a relatively blunt releasing `angle with respect to the aXis of the mechanism, whereas the face 26 of the shoe C extends at a relatively keen angle thereto.

iouter end face 28 bearing directly on the inner surface ofthe front follower 15. At

. t-he'inner end, the wedge block D has three wedge faces 126-126, symmetrically arranged about the axis. of. thermechanism. Two of the wedge faces 126 co-operate with the wedge faces 26 of the shoes C, and are also inclinedata relatively blunt releasing angle ywith reference to the axis of thefmech-Y anisin, while the remaining wedo'e face 126 cooperates with the wedgev face .26 of .the shoes C andis disposed ata relatively keen, wedge angle to said axis.

The intermediate friction blocks E, E and E .are in the form of castings and of like construction except as hereinafter pointed out'. 4Each ofthe two blocks E has an outer face 127 correspondingly inclined to and adapteudito co-operate witlrthe face 27 of one ofthe lfriction shoes C and the block E also has an outer face 127 correspondingly inclined to and adapted to co-operate with the face 27 of the friction block C. The twoyfriction slices E each have an inner face 29 correspondingly inclined to and vadapted to coi-operate with the corresponding blunt face 126 of the wedge block D, and the friction block E also has an inner face 129 cor.- respondingly inclined to and adapted .to cooperate with the keen wedge face 126 of the block D.

The main spring follower F is in the form of a heavy rectangular plate, and bears directly on theA outer ends ofthe twin arranged spring .resistance elements J. The

snrino follower F has a 1)luralit of forl n l y wardly projecting bosses 30, symmetrically arranged around'the axis of the mechanism, six bosses 80 being so shownv in the embodiment of the invention vas illustrated in the drawings. y

The auxiliary follower G, which is also in the form of a rectangular plate, is provided wit-h an annular groove 31 at the front side thereof, adapted to accommodate the inner end of the friction shell. As clearlyshown iinA Figur-e 1, the outer edge portion of the follower G normally engages the rearf'faces of the ribs 22. rlhe plate -G .iswof such v a height as to be fre-ely=accoin1nodated between `the top and bottom walls 17 and 18l of the spring cage.

The wear plate H, which is preferably in* the form of a steel Adisc is interposed between the auxiliary follower and the inner ends-of the intermediate friction blocks E, E and E, the outer face of 'the plate being n inclined outwardly laterally from the axisA of the gear `and engaging Ythe correspondingly infY cliiied -ends of )the intermediate friction blocks.

The par-ts of the mechanisnrare held in assembled relation and Amaintainedof overall uniform length by the retainer bolt K, which has its front and rear ends anchored respectively to the wedgel block D andthe auxiliary wedge follower G, thehead at-the rear endfof the bo-lt being seated in' arecessed boss 32 at the rear side. of thev follower and the nutat the forward end of the bolt being accommodated within the hollow Vportion of the wedge block. VWhen the parts are assembled, the retainer bolt, in conjunction witlrtlie auxiliary follower G, wedge-friction=shoes, intermediate friction blocks and wedge, serves to prevent separationofthe friction shell in a vertical direction with reference .to the spring cage casting, vthe auxiliary follower G being held against movementin a vertical plane between the top and bottom walls 17 and 18 of the spring cage. `Gutward movement of the friction shoes C, C and C with reference to the friction shell is limited by lugsv 33 engaging shoulders 3e `en the friction shell, each shoe being preferably provided vwith a single lug 33accommodated in a slot 35, having a limiting'shoulder 34 at the frontend thereof.4

As clearly shown inFigure 1, the front' ends of the bosses 30 ofthe `follower Fbear directly on therear surface ofthe wear plate H, extending through the auxiliary followers G, the latter being provided with openings to accommodate the same. The lugs serve to maintain the spring follower F in spaced relation with reference to the auxiliary follower Gy. The clearance provided between the spring folio .ier Fand Vthe auxiliary follower G permits outward movement of the former with reference to the latter as the various wedge and friction faces become worn. y

The main spring resistance J comprises twin arranged elements,` 'each including a hea- Vy outerv coil, and a relatively lighterV inner coil, the opposite ends of the coils bearand the inner surface of the end wall 20 of the spring cage casting. lVith the parts in normalcondition as shown in Figure 1, 'it is evident that there will be no true wedging or spreading action from the wedge D to the shoes C, C and C, due to the intermediate friction blocks hold-` ing the wedge in spaced relation to the shoes. During compression of the mechanism, the wedge will'be carried inwardly with the follower 15 and the actuating force will be transmitted through the intermediate elements'l, E and ll, wear plate H and spring follower F to the main springs d. Due to the wed-ging action between the wedge Dy and the intermediate friction blocks, the lat-l` ter will before-ed laterally |apart, slipping ing respectively' on' theY spring follower F on the faces 27 of the' friction-shoes. It will las mechanism, ,ai differential' action will be had,

the'spring follower being movedl inwardly atalesser rate than the wedge Gpthereby effecting a' relatively' slow compression of the main spring resistance elements J. The parts are preferably so proportioned that tliezfollower Fwill, during this time, move a distance about one-half the movement of i the wedge.V The preliminary action just de-l scribed willV continue until the blocks E,E

and Ehave 'been moved inwardly to such an'extent that the wedge. faces lof `the wedge block will comeinto engagement with tliewedge faces 26 of the shoes, whereupon the shoes will be forced laterally apart.' 1 into intimate" Contact Withthe friction surfaces of the shell and carriedrearwardly'in runisony .with tliefintermediate friction blocks, wear plate H and follower F. During the remainder of the compression'.'stroke, the Vparts inst referred to will be carried in! iviai'dly )practically as a unit,V there being substantially vlittle further "relative movement between vthe blocks and the friction-wedgeshoes except that due to the taper ofthe frictionshell. This 'action will continue either iiiitil,tlie actuating force-is'i'ednced, or until the main followerrl comes into engagement withy the outer `end off the'friction` shell, whereupon the pressure `will be transmitted through the friction'shell and spring cage casting A,di iectly to the corresponding stop lugs of the draft sills. VDueto theemployment of the blunt and keen sets of wedge faces on 'thel shoes'and 'main wedge, I obtain'a very high wedging action' during the-latter part'of the compression" stroke, since the .keen "angle Wedge faces may be made relatively acute without danger of the' partssticking, the bluntwedge faces acting more or-less as .saf'ety valves toV prevent sticking.

It will be understood by thoseskilledin the art thatmy particular improvements are capable-ofnse in a mechanism employing either the blunt and keen angle system of` wedge faces, or wedge faces which are all of the same angle with respect to the axis of the mechanism.

I have .herein shown and described what I now consider the preferred manner of carrying out my invention, but the same Vis merely illustrative and Icontemplate all changes and modifications that come within the scope of the Vclaims appended hereto.

I claim: Y f 1. In a Vfriction shock absorbing mechanism, the combination with a friction shell vhaving interior opposed friction surfaces; of a. spring resistance; a pluralityv of fric-4V tion-shoes co-operable with said friction surfaces; a pressure-transniitting wedge means;

and separate means interposed between the Wedge and shoes and having lateral engagement therewith for holding the former from intermediate frictioii effective wedgi'ng'eiigagement 'with the shoes .i I

under ,full release, but permitting the wedge ,toengage theshoesafter a predetermined compression ofthe mechanism. i 2'; In a friction shock absorbing mecha-l v nism, the combination with a friction shell having interior opposed friction surfaces;

having interior friction surfaces;l of a plu-v ralit vof'friction-wedofe-shoes co'-o eratinw.

Y a .s

with the friction surfaces'of the. shell, each blocks for'holding said wedge normally out of contact with the friction shoes, said blocksv each having a wedge face cooperatingrwith .one ofthe wedgev faces of one of saidV shoes.

. 4. In a friction shock absorbing mechan of said shoes having a pair of wedge faces; a lmain springresistance; wedgafriction .yi

nism, the combination with a column 'elel ment havingfrietion surfaces;y o f a plurality of friction-shoes cooperating with said column element,A SadshOeseach having a wedge facefand a friction face inclined at an angle to the axis of theinechanism; fric- `tion blocks each having-a wedge face and a frictionV face, said last named face co-operating with the friction face k'of one ofsaid shoes; a pressure-transmitting member hav ing apluralityoflwedge faces, each of said last named Wedge faces lhavingA a vsection thereof engaging the wedge face of one of said frictionl blocks and. a section normallyspaced-from the Awedge face of one'of'said a predetermined compression of the mechafv nism; and ak main spring resistance'oppos ing movement of said shoes and blocks inwardly off the mechanism.

5. vIn a yfriction shock absorbing mecha` nisin, the combination withv a column element having friction suifaces;.of a plurality of friction-shoes co-operating with said column element, said shoes each having an.

outer wedge face and an inner friction face, said last named face 'being inclined reversely to said outer face; a wedgepressure-trans mitting member having aplnrality ofwedge faces adapted` to co-operate with the wedge faces of said shoes after a predetermined compression of the mechanism; friction elements interposed between each wedge face of said pressure-transmitting member and the inner face of the corresponding'shoe and shoesandadapted to engage the same after adapted tofslide .thereon during initial compression of Ithe mechanism, sai-d friction elements normally holding said .wedge member spaced from the shoes; and/amain spring resistance opposing-inward movement of said shoes and elements.

6. In a friction shock absorbing mechanism, thecombinationfwith a frictionv shell having interior, inwardly converging friction surfaces; of a plurality of frictionshoes Ico-operating with the friction surfaces of Vtheshell7 said .shoes having outer wedge faces converging inwardly of the mechanism and lin ner faces; diverging inwardly ofthe mechanism; a pressure-trans mitting member having a Vplurality of wedge facesI adapted 'to ico-operate with the wedge faces of the shoes; a plurality of friction elements each :li-ating a frictionand awedge face, the friction 'faces of said elements en gaging the innerfaces of the shoes `andthe wedge faces thereof :engaging `the V,wedge faces of said member; andfa -main spring 'resisting movement of said shoesand elements, said'spring normally holding said elements projected to :hold said member ifree from ef fe'ctive' ywedging engagen'ient with the shoes when `thf'efmechanisrnis yin full release and permitting co-operative engagementfof ysaid member Yandshoes after aV predetermined relative ymovement of said elements and 7.A In y a friction shock absorbing mech anis1n,the combination with a friction column clement.; of :a main spring lresistance; anda friction wedge systeinco-operating withV said column element, said system `in- Y clfuding wedge-friction-shoes, friction fbloclrs andy a main wedge Vmember; said friction L blocks-holding said wedge member out of VContact with the shoes during a predeteri mined initial vportion of the compression stroke.

8. In la friction. shock absorbing mechanism; the combination with a frictionshell;

a :spring resistance .within the shell; a wedgefrictionsysteni co-operating with the shell;

'said systemincluding friction shoes, a .pres-v sure-transmitting wedge Y and dierential elements adapted to initially receive the actuating'force directly from'the wedge and hold Athe wedge yout ofengagement with the' shoes during initial action of the *mecha* nism and permit operative wedging engager ment-of said wedge and shoes after a prede'- termmed differential movementof Vsaid element and wedge lto transmit the actuating force directly to the shoes. v

9. In a friction shock absorbingmechanism; the combination with a frictionelement; of a friction wedge system cooperating with said element, said system including a wedgepressure-transmitting device and co-acting frictiony members having ldifferential movement, certain of which are adapted friction shell, said shell and cage'having co-operating means thereon for .preventing relative longitudinal movement thereof; wedge frietionzmeans co-operating with the shell; a main spring follower; andan auX- iliary follower within the cage, said last named follower being held againstdisplacement in a plane at right angles to the axis of the mechanism; and anchoring means carried by said last `named follower for pre-r venting relative movement of the shell and follower in parallel planes.

In witness thatlI claim the .foregoing I have hereunto subscribed myname this 18th day of February,` 1925)'.

JOI-IN F.' OvCONNOR. 

